linux/include
Tony Luck c0ab7ffce2 x86/mce: Recover from poison found while copying from user space
Existing kernel code can only recover from a machine check on code that
is tagged in the exception table with a fault handling recovery path.

Add two new fields in the task structure to pass information from
machine check handler to the "task_work" that is queued to run before
the task returns to user mode:

+ mce_vaddr: will be initialized to the user virtual address of the fault
  in the case where the fault occurred in the kernel copying data from
  a user address.  This is so that kill_me_maybe() can provide that
  information to the user SIGBUS handler.

+ mce_kflags: copy of the struct mce.kflags needed by kill_me_maybe()
  to determine if mce_vaddr is applicable to this error.

Add code to recover from a machine check while copying data from user
space to the kernel. Action for this case is the same as if the user
touched the poison directly; unmap the page and send a SIGBUS to the task.

Use a new helper function to share common code between the "fault
in user mode" case and the "fault while copying from user" case.

New code paths will be activated by the next patch which sets
MCE_IN_KERNEL_COPYIN.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201006210910.21062-6-tony.luck@intel.com
2020-10-07 11:29:41 +02:00
..
acpi ACPI updates for 5.9-rc1 2020-08-03 20:37:22 -07:00
asm-generic iomap: constify ioreadX() iomem argument (as in generic implementation) 2020-08-14 19:56:57 -07:00
clocksource include/: replace HTTP links with HTTPS ones 2020-08-12 10:57:59 -07:00
crypto mm, treewide: rename kzfree() to kfree_sensitive() 2020-08-07 11:33:22 -07:00
drm Linux 5.8 2020-08-11 11:58:31 +10:00
dt-bindings Here's some more updates that missed the last pull request because I 2020-08-12 12:19:49 -07:00
keys It's been a busy cycle for documentation - hopefully the busiest for a 2020-08-04 22:47:54 -07:00
kunit
kvm
linux x86/mce: Recover from poison found while copying from user space 2020-10-07 11:29:41 +02:00
math-emu
media media updates for v5.9-rc1 2020-08-07 13:00:53 -07:00
memory
misc ocxl: Address kernel doc errors & warnings 2020-07-29 23:47:52 +10:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-08-13 20:03:11 -07:00
pcmcia
ras
rdma RDMA 5.9 merge window pull request 2020-08-06 16:43:36 -07:00
scsi
soc include/: replace HTTP links with HTTPS ones 2020-08-12 10:57:59 -07:00
sound ALSA: hda: Add dma stop delay variable 2020-08-05 12:27:47 +02:00
target scsi: target: Make iscsit_register_transport() return void 2020-08-04 20:56:56 -04:00
trace Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-08-13 20:03:11 -07:00
uapi NFS client updates for Linux 5.9 2020-08-15 08:26:55 -07:00
vdso lib/vdso: Allow to add architecture-specific vdso data 2020-08-06 10:57:30 +02:00
video
xen xen: branch for v5.9-rc1b 2020-08-14 13:34:37 -07:00